Timing acquisition module for wireless power transmission

ABSTRACT

A Timing Acquisition Module (TAM) associated with a wireless power transmission systems (WPTS) is disclosed herein. The TAM is configured to receive encoded beacons broadcast by wireless power receiver clients requesting power on demand. The TAM decodes the encoded beacons to identify respective client broadcast and notifies the WPTS that a client is requesting power. In turn, the WPTS transmits wireless power signals to the client. The WPTS and client may use separate beacons or signals to command the client to broadcast its WPTS beacon. Phases of a beacon are detected by antennas in the WPTS antenna array, and based on the beacon, the wireless power signals are transmitted from the WPTS to the client. Multiple apparatus including a combination of a WPTS and TAM may be implemented in a wireless power environment in a cooperative manner, enabling a client to move within the environment while supporting power on demand.

RELATED APPLICATION

The subject patent application is a continuation of, and claims priorityto, U.S. patent application Ser. No. 16/244,013, filed Jan. 9, 2019, andentitled “TIMING ACQUISITION MODULE FOR WIRELESS POWER TRANSMISSION,”the entirety of which application is hereby incorporated by referenceherein.

BACKGROUND INFORMATION

The use of wireless communication in today's environments is ubiquitous.It seems that everyone has at least one “smart” wireless device, such asa smart phone or tablet, and many have other types of mobile computingdevices, such as laptops, notebooks, Chromebooks, etc., that supportwireless communication. In addition to cellular and mobile computing,wireless communication technologies are used for other purposes, such asaudio systems, portable telephone systems, screen casting, andpeer-to-peer communication to name a few.

Substantially all of the forgoing wireless devices are or can be poweredby rechargeable batteries. Conventional rechargeable battery chargersrequire access to a power source such as an alternating current (AC)power outlet, which may not always be available or convenient. Therehave recently been techniques introduced for so-called “wireless”charging using magnetic or inductive charging-based solutions in whichthe wireless device is placed in close proximity to the charging unit.However, during charging the wireless device must (generally) be placedon the charging base.

Wireless power transmission at larger distances often use more advancedmechanisms, such as transmission via radio frequency (RF) signals,ultrasonic transmissions, and laser powering, to name a few, each ofwhich presents a number of unique hurdles to commercial success. Ofthese, the most viable for commercial deployment are wireless powertransmission systems (WPTS) employing RF signals. Such WPTS may(generally) utilize portions of licensed and unlicensed RF spectrum,including, but not limited to 2.4 GHz and 5/5.8 GHz radio bands.

In the context of RF transmission within a common residence, commercialbuilding, or other habited environment, there are many reasons to limitthe RF exposure levels of the transmitted signals. Consequently, powerdelivery via RF signals is constrained to relatively low power levels.Due to this low energy transfer rate, it is imperative that the systemis efficient.

One technique for providing power to clients using RF signals is to usea time-slot based scheme, where RF power signals are directed towardspecific clients during corresponding time slots. This approach includesa master bus controller directing clients when to beacon and directingthe antenna elements of the WPTS when to take a sample of incomingbeacons and determine the complex phase of the beacons received from theclients. The master bus controller then tells the antenna elements tocompute the complex conjugate and store the result as a path back to theclient for providing power signals to the clients. The master buscontroller then directs the next time slot to the next client. Whilethis system may enable the clients to receive the power signals at aspecified time slot, this technique requires a large volume ofcommunications between the master bus controller, the antenna boards,and the clients as timing of client communications must be individuallycoordinated by the master bus controller. Therefore, this techniquedecreases available time slots that may be used for additional power.

Other typical techniques may include the master bus controllerpre-calculating a client power schedule for the subsequent time intervaland sending the schedule to both the clients and antenna boards. In thismethod, the master bus controller allocates a start time and theprearranged beaconing schedule to determine which clients receive powersignals and at which time slot. While this method is more time efficientthan previous power beaconing models, time slots that may have been usedfor sending power signals are allocated to sending communicationsincluding the prearranged schedules. Additionally, this technique doesnot allow clients to have any control over which transmission system theclient may receive power from and therefore, clients are unable to moveor roam while listening for beacons or receiving power beacons.Essentially, the clients become active power receivers since they needto be aware of when the communication beacons are transmitted to be ableto then harvest the power that was available based on the time schedule.

Accordingly, a need exists for technology that overcomes thedemonstrated problems outlined above, as well as one that providesadditional benefits. The examples provided herein of some prior orrelated systems and their associated limitations are intended to beillustrative and not exclusive. Other limitations of existing or priorsystems will become apparent to those of skill in the art upon readingthe following Detailed Description.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and many of the attendant advantages of thisinvention will become more readily appreciated as the same becomesbetter understood by reference to the following detailed description,when taken in conjunction with the accompanying drawings, wherein likereference numerals refer to like parts throughout the various viewsunless otherwise specified:

FIG. 1 depicts an example wireless power delivery environmentillustrating wireless power delivery from one or more wireless powertransmission systems to various wireless devices within the wirelesspower delivery environment in accordance with some embodiments;

FIG. 2 depicts a sequence diagram illustrating example operationsbetween a wireless power transmission system and a wireless receiverclient for commencing wireless power delivery in accordance with someembodiments;

FIG. 3 depicts a block diagram illustrating example components of awireless power transmission system in accordance with some embodiments;

FIG. 4 depicts a block diagram illustrating example components of awireless power receiver client in accordance with some embodiments;

FIGS. 5A and 5B depict diagrams illustrating an example multipathwireless power delivery environment in accordance with some embodiments;

FIG. 6 is a diagram illustrating an example determination of an incidentangle of a wavefront in accordance with some embodiments;

FIG. 7 is a diagram illustrating an example minimum omnidirectionalwavefront angle detector in accordance with some embodiments;

FIG. 8 is a schematic diagram of a Timing Acquisition Module (TAM) andhost/CCB interface, according to one embodiment;

FIG. 9 is a schematic diagram illustrating further details of thereceiver and transmitter circuitry for the TAM of FIG. 8, according toone embodiment;

FIG. 10 is a flowchart illustrating operations for establishingcommunication with a wireless power receiver client and providing a codeto be used by the client when broadcasting its encoded TAM beacon,according to one embodiment;

FIG. 11 is a schematic diagram of a WPTS tile including an integratedTAM, according to one embodiment'

FIG. 12 is a flowchart illustrating operations performed to establishcommunication between a WPTS and a wireless power receiver client andassociated configuration operations, according to one embodiment;

FIG. 13 is a message flow diagram illustrating messages that areexchanged between a WPTS and a TAM during initialization of a WPTS tile,according to one embodiment;

FIG. 14 is a message/signal flow diagram illustrating operations andmessage flows associated with implementation of a wireless power-ondemand scheme, according to one embodiment; and

FIG. 15 is a schematic diagram of a wireless power delivery environmentincluding two WPTS tiles providing power to wireless power receiverclients in three exemplary wireless devices.

DETAILED DESCRIPTION

Embodiments of a Timing Acquisition Module (TAM) configured for use inor associated with a WPTS and associated methods, apparatus, and systemsare described herein. In the following description, numerous specificdetails are set forth to provide a thorough understanding of embodimentsof the invention. One skilled in the relevant art will recognize,however, that the invention can be practiced without one or more of thespecific details, or with other methods, components, materials, etc. Inother instances, well-known structures, materials, or operations are notshown or described in detail to avoid obscuring aspects of theinvention.

Reference throughout this specification to “one embodiment” or “anembodiment” means that a particular feature, structure, orcharacteristic described in connection with the embodiment is includedin at least one embodiment of the present invention. Thus, theappearances of the phrases “in one embodiment” or “in an embodiment” invarious places throughout this specification are not necessarily allreferring to the same embodiment. Furthermore, the particular features,structures, or characteristics may be combined in any suitable manner inone or more embodiments.

For clarity, individual components in the Figures herein may also bereferred to by their labels in the Figures, rather than by a particularreference number. Additionally, reference numbers referring to aparticular type of component (as opposed to a particular component) maybe shown with a reference number followed by “(typ)” meaning “typical.”It will be understood that the configuration of these components will betypical of similar components that may exist but are not shown in thedrawing Figures for simplicity and clarity or otherwise similarcomponents that are not labeled with separate reference numbers.Conversely, “(typ)” is not to be construed as meaning the component,element, etc. is typically used for its disclosed function, implement,purpose, etc.

The terms used in this specification generally have their ordinarymeanings in the art, within the context of the disclosure, and in thespecific context where each term is used. Certain terms that are used todescribe the disclosure are discussed below, or elsewhere in thespecification, to provide additional guidance to the practitionerregarding the description of the disclosure. For convenience, certainterms may be highlighted, for example using italics and/or quotationmarks. The use of highlighting has no influence on the scope and meaningof a term; the scope and meaning of a term is the same, in the samecontext, whether or not it is highlighted. It will be appreciated thatsame thing can be said in more than one way.

Consequently, alternative language and synonyms may be used for any oneor more of the terms discussed herein, nor is any special significanceto be placed upon whether or not a term is elaborated or discussedherein. Synonyms for certain terms are provided. A recital of one ormore synonyms does not exclude the use of other synonyms. The use ofexamples anywhere in this specification, including examples of any termsdiscussed herein, is illustrative only, and is not intended to furtherlimit the scope and meaning of the disclosure or of any exemplifiedterm. Likewise, the disclosure is not limited to various embodimentsgiven in this specification.

Without intent to further limit the scope of the disclosure, examples ofinstruments, apparatus, methods and their related results according tothe embodiments of the present disclosure are given below. Note thattitles or subtitles may be used in the examples for convenience of areader, which in no way should limit the scope of the disclosure. Unlessotherwise defined, all technical and scientific terms used herein havethe same meaning as commonly understood by one of ordinary skill in theart to which this disclosure pertains. In the case of conflict, thepresent document, including definitions, will control.

In accordance with aspects of the embodiments described herein, a TAM isdisclosed for implementation with or integrated in a WPTS. The TAMprovides facilities for enhancing the features and capabilities of aWPTS. For example, under some embodiments, wireless power receiverclients can request “power on demand” using a TAM, wherein the TAM, inconjunction with a WPTS, is used to control delivery of wireless powersignals to wireless power receiver clients requesting power. Moreover,these enhancements may be implemented in shared wireless mediumenvironments, such as Wi-Fi™ WLANs and in a manner that co-exists withexisting equipment.

To better understand how to implement the embodiments of TAMs andrelated innovations disclosed herein, an overview of the operation andarchitecture of an exemplary WPTS is now presented.

I. Wireless Power Transmission System Overview/Architecture

FIG. 1 depicts a block diagram including an example wireless powerdelivery environment 100 illustrating wireless power delivery from oneor more wireless power transmission systems (WPTS) 101 a-n (alsoreferred to as “wireless power delivery systems”, “antenna arraysystems” and “wireless chargers”) to various wireless devices 102 a-nwithin the wireless power delivery environment 100, according to someembodiments. More specifically, FIG. 1 illustrates an example wirelesspower delivery environment 100 in which wireless power and/or data canbe delivered to available wireless devices 102 a-102 n having one ormore wireless power receiver clients 103 a-103 n (also referred toherein as “clients” and “wireless power receivers”). The wireless powerreceiver clients are configured to receive and process wireless powerfrom one or more wireless power transmission systems 101 a-101 n.Components of an example wireless power receiver client 103 are shownand discussed in greater detail with reference to FIG. 4.

As shown in the example of FIG. 1, the wireless devices 102 a-102 ninclude mobile phone devices and a wireless game controller. However,the wireless devices 102 a-102 n can be any device or system that needspower and is capable of receiving wireless power via one or moreintegrated power receiver clients 103 a-103 n. As discussed herein, theone or more integrated power receiver clients receive and process powerfrom one or more wireless power transmission systems 101 a-101 n andprovide the power to the wireless devices 102 a-102 n (or internalbatteries of the wireless devices) for operation thereof.

Each wireless power transmission system 101 can include multipleantennas 104 a-n, e.g., an antenna array including hundreds or thousandsof antennas, which are capable of delivering wireless power to wirelessdevices 102. In some embodiments, the antennas are adaptively-phasedradio frequency (RF) antennas. The wireless power transmission system101 is capable of determining the appropriate phases with which todeliver a coherent power transmission signal to the power receiverclients 103. The array is configured to emit a signal (e.g., continuouswave or pulsed power transmission signal) from multiple antennas at aspecific phase relative to each other. It is appreciated that use of theterm “array” does not necessarily limit the antenna array to anyspecific array structure. That is, the antenna array does not need to bestructured in a specific “array” form or geometry. Furthermore, as usedherein he term “array” or “array system” may be used include related andperipheral circuitry for signal generation, reception and transmission,such as radios, digital logic and modems. In some embodiments, thewireless power transmission system 101 can have an embedded Wi-Fi hubfor data communications via one or more antennas or transceivers.

The wireless devices 102 can include one or more receive power clients103. As illustrated in the example of FIG. 1, power delivery antennas104 a-104 n are shown. The power delivery antennas 104 a are configuredto provide delivery of wireless radio frequency power in the wirelesspower delivery environment. In some embodiments, one or more of thepower delivery antennas 104 a-104 n can alternatively or additionally beconfigured for data communications in addition to or in lieu of wirelesspower delivery. The one or more data communication antennas areconfigured to send data communications to and receive datacommunications from the power receiver clients 103 a-103 n and/or thewireless devices 102 a-102 n. In some embodiments, the datacommunication antennas can communicate via Bluetooth™, Wi-Fi™ (includingbut not limited to Institute of Electrical and Electronics Engineers(IEEE) 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac), ZigBee™, etc.Other data communication protocols are also possible.

Each power receiver client 103 a-103 n includes one or more antennas(not shown) for receiving signals from the wireless power transmissionsystems 101 a-101 n. Likewise, each wireless power transmission system101 a-101 n includes an antenna array having one or more antennas and/orsets of antennas capable of emitting continuous wave or discrete (pulse)signals at specific phases relative to each other. As discussed above,each the wireless power transmission systems 101 a-101 n is capable ofdetermining the appropriate phases for delivering the coherent signalsto the power receiver clients 102 a-102 n. For example, in someembodiments, coherent signals can be determined by computing the complexconjugate of a received beacon (or calibration) signal at each antennaof the array such that the coherent signal is phased for deliveringpower to the particular power receiver client that transmitted thebeacon (or calibration) signal.

Although not illustrated, each component of the environment, e.g.,wireless device, wireless power transmission system, etc., can includecontrol and synchronization mechanisms, e.g., a data communicationsynchronization module. The wireless power transmission systems 101a-101 n can be connected to a power source such as, for example, a poweroutlet or source connecting the wireless power transmission systems to astandard or primary alternating current (AC) power supply in a building.Alternatively, or additionally, one or more of the wireless powertransmission systems 101 a-101 n can be powered by a battery or viaother mechanisms, e.g., solar cells, etc.

The power receiver clients 102 a-102 n and/or the wireless powertransmission systems 101 a-101 n are configured to operate in amultipath wireless power delivery environment. That is, the powerreceiver clients 102 a-102 n and the wireless power transmission systems101 a-101 n are configured to utilize reflective objects 106 such as,for example, walls or other RF reflective obstructions within range totransmit beacon (or calibration) signals and/or receive wireless powerand/or data within the wireless power delivery environment. Thereflective objects 106 can be utilized for multi-directional signalcommunication regardless of whether a blocking object is in the line ofsight between the wireless power transmission system and the powerreceiver client.

As described herein, each wireless device 102 a-102 n can be any systemand/or device, and/or any combination of devices/systems that canestablish a connection with another device, a server and/or othersystems within the example environment 100. In some embodiments, thewireless devices 102 a-102 n include displays or other outputfunctionalities to present data to a user and/or input functionalitiesto receive data from the user. By way of example, a wireless device 102can be, but is not limited to, a video game controller, a serverdesktop, a desktop computer, a computer cluster, a mobile computingdevice such as a notebook, a laptop computer, a handheld computer, amobile phone, a smart phone, a tablet, a PDA, a Blackberry device, aTreo, and/or an iPhone, etc. By way of example and not limitation, thewireless device 102 can also be any wearable device such as watches,necklaces, rings or even devices embedded on or within the customer.Other examples of a wireless device 102 include, but are not limited to,safety sensors (e.g., fire or carbon monoxide), electric toothbrushes,electronic door lock/handles, electric light switch controller, electricshavers, etc.

Although not illustrated in the example of FIG. 1, the wireless powertransmission system 101 and the power receiver clients 103 a-103 n caneach include a data communication module for communication via a datachannel. Alternatively, or additionally, the power receiver clients 103a-103 n can direct the wireless devices 102.1-102.n to communicate withthe wireless power transmission system via existing data communicationsmodules. In some embodiments the beacon signal, which is primarilyreferred to herein as a continuous waveform, can alternatively oradditionally take the form of a modulated signal.

FIG. 2 is a sequence diagram 200 illustrating example operations betweena wireless power delivery system (e.g., WPTS 101) and a wireless powerreceiver client (e.g., wireless power receiver client 103) forestablishing wireless power delivery in a multipath wireless powerdelivery, according to a conventional approach using time-slots.Initially, communication is established between the wireless powertransmission system 101 and the power receiver client 103. The initialcommunication can be, for example, a data communication link that isestablished via one or more antennas 104 of the wireless powertransmission system 101. As discussed, in some embodiments, one or moreof the antennas 104 a-104 n can be data antennas, wireless powertransmission antennas, or dual-purpose data/power antennas. Variousinformation can be exchanged between the wireless power transmissionsystem 101 and the wireless power receiver client 103 over this datacommunication channel. For example, wireless power signaling can be timesliced (e.g., using time slots) among various clients in a wirelesspower delivery environment. In such cases, the wireless powertransmission system 101 can send beacon schedule information, e.g.,Beacon Beat Schedule (BBS) cycle, power cycle information, etc., so thatthe wireless power receiver client 103 knows when to transmit(broadcast) its beacon signals and when to listen for power, etc.

Continuing with the example of FIG. 2, the wireless power transmissionsystem 101 selects one or more wireless power receiver clients forreceiving power and sends the beacon schedule information to the selectpower receiver clients 103. The wireless power transmission system 101can also send power transmission scheduling information so that thepower receiver client 103 knows when to expect (e.g., a window of time)wireless power from the wireless power transmission system. The powerreceiver client 103 then generates a beacon (or calibration) signal andbroadcasts the beacon during an assigned beacon transmission window (ortime slice) indicated by the beacon schedule information, e.g., BeaconBeat Schedule (BBS) cycle. As discussed herein, the wireless powerreceiver client 103 include one or more antennas (or transceivers) whichhave a radiation and reception pattern in three-dimensional spaceproximate to the wireless device 102 in which the power receiver client103 is embedded.

The wireless power transmission system 101 receives the beacon from thepower receiver client 103 and detects and/or otherwise measures thephase (or direction) from which the beacon signal is received atmultiple antennas. The wireless power transmission system 101 thendelivers wireless power to the power receiver client 103 from themultiple antennas 103 based on the detected or measured phase (ordirection) of the received beacon at each of the corresponding antennas.In some embodiments, the wireless power transmission system 101determines the complex conjugate of the measured phase of the beacon anduses the complex conjugate to determine a transmit phase that configuresthe antennas for delivering and/or otherwise directing wireless power tothe power receiver client 103 via the same path over which the beaconsignal was received from the power receiver client 103.

In some embodiments, the wireless power transmission system 101 includesmany antennas; one or more of which are used to deliver power to thepower receiver client 103. The wireless power transmission system 101can detect and/or otherwise determine or measure phases at which thebeacon signals are received at each antenna. The large number ofantennas may result in different phases of the beacon signal beingreceived at each antenna of the wireless power transmission system 101.As discussed above, the wireless power transmission system 101 candetermine the complex conjugate of the beacon signals received at eachantenna. Using the complex conjugates, one or more antennas may emit asignal that takes into account the effects of the large number ofantennas in the wireless power transmission system 101. In other words,the wireless power transmission system 101 can emit a wireless powertransmission signal from the one or more antennas in such a way as tocreate an aggregate signal from the one or more of the antennas thatapproximately recreates the waveform of the beacon in the oppositedirection. Said another way, the wireless power transmission system 101can deliver wireless RF power to the client device via the same pathsover which the beacon signal is received at the wireless powertransmission system 101. These paths can utilize reflective objects 106within the environment. Additionally, the wireless power transmissionsignals can be simultaneously transmitted from the wireless powertransmission system 101 such that the wireless power transmissionsignals collectively match the antenna radiation and reception patternof the client device in a three-dimensional (3D) space proximate to theclient device.

As shown, the beacon (or calibration) signals can be periodicallytransmitted by power receiver clients 103 within the power deliveryenvironment according to, for example, the BBS, so that the wirelesspower transmission system 101 can maintain knowledge and/or otherwisetrack the location of the power receiver clients 103 in the wirelesspower delivery environment. The process of receiving beacon signals froma wireless power receiver client at the wireless power transmissionsystem and, in turn, responding with wireless power directed to thatparticular client is referred to herein as retrodirective wireless powerdelivery.

Furthermore, as discussed herein, wireless power can be delivered inpower cycles defined by power schedule information. A more detailedexample of the signaling required to commence wireless power delivery isdescribed now with reference to FIG. 3.

FIG. 3 depicts a block diagram illustrating example components of awireless power transmission system 300 in accordance with someembodiments. As illustrated in the example of FIG. 3, wireless powertransmission system 300 includes a computer controller board (CCB) andmultiple mezzanine boards that collectively comprise the antenna array.The CCB includes control logic 310, an external data interface (I/F)315, an external power interface 320, a TAM interface 325, acommunication block 330, a proxy 340, and a signal generator 350. Eachantenna array board 360 includes switches 362 a-362 n, phase shifters364 a-364 n, power amplifiers 366 a-366 n, and antenna arrays 368 a-368n.

The configuration of wireless power transmission system 300 illustratedin FIG. 3 is exemplary and non-limiting, and may include additionalcomponents that are not shown for simplicity and clarity. In addition,some components may be omitted. For example, in some embodiments onlyone of communication block 330 or proxy 340 may be included.

The control logic 310 is configured to provide control and intelligenceto the array components. The control logic 310 may comprise one or moreprocessors (e.g., as depicted by processor 312, FPGAs, memory units(e.g., as depicted by memory 314), etc., and direct and control thevarious data and power communications. More generally, control logic maybe implemented using embedded logic configured to implement thefunctionality described for control logic herein, includinghardware-based embedded logic (e.g., FPGA, one or more digital signalprocessors (DSP), one or more application specific integrated circuits(ASICs), and a combination of hardware- and software-based embeddedlogic, such as one or more processing elements configured to executedsoftware and/or firmware to implement the functionality described forcontrol logic herein.

Signal generator 350 can compute a signal wave comprising power or datacommunications on a data carrier frequency. The signal wave can beBluetooth™, Wi-Fi™, ZigBee™, etc., including combinations or variationsthereof, as well as proprietary signal waves. In some embodiments, logic310 can also determine a transmission configuration comprising aphase-shift based on the encoded beacon signal received from receiverdevice 370.

The communication block 330 can direct data communications on a datacarrier frequency, such as the base signal clock for clocksynchronization. The data communications can be Bluetooth™, Wi-Fi™,ZigBee™, etc., including combinations or variations thereof. Likewise,the proxy 340 can communicate with clients via data communications asdiscussed herein. The data communications can be, by way of example andnot limitation, Bluetooth™ Wi-Fi™, ZigBee™, etc. Other communicationprotocols are possible.

In some embodiments, the control logic 310 can also facilitate and/orotherwise enable data aggregation for Internet of Things (IoT) devices.In some embodiments, wireless power receiver clients can access, trackand/or otherwise obtain IoT information about the device in which thewireless power receiver client is embedded and provide that IoTinformation to the wireless power transmission system 300 over a dataconnection. This IoT information can be provided to via an external datainterface 315 to a central or cloud-based system (not shown) where thedata can be aggregated, processed, etc. For example, the central systemcan process the data to identify various trends across geographies,wireless power transmission systems, environments, devices, etc. In someembodiments, the aggregated data and or the trend data can be used toimprove operation of the devices via remote updates, etc. Alternatively,or additionally, in some embodiments, the aggregated data can beprovided to third party data consumers. In this manner, the wirelesspower transmission system acts as a Gateway or Enabler for the IoTs. Byway of example and not limitation, the IoT information can includecapabilities of the device in which the wireless power receiver clientis embedded, usage information of the device, power levels of thedevice, information obtained by the device or the wireless powerreceiver client itself, e.g., via sensors, etc.

The external power interface 320 is configured to receive external powerand provide the power to various components. In some embodiments, theexternal power interface 320 may be configured to receive a standardexternal 24 Volt power supply. In other embodiments, the external powerinterface 320 can be, for example, 120/240 Volt AC mains to an embeddedDC power supply which sources the required 12/24/48 Volt DC to providethe power to various components. Alternatively, the external powerinterface could be a DC supply which sources the required 12/24/48 VoltsDC. Alternative configurations are also possible.

Switches 362 a-362 n may be activated to transmit power and receiveclient beacon signals when the switches are closed, as can be seen bythe connected lines inside each of switches 362 a-362 n. On the otherhand, switches 362 a-362 n may be deactivated for power transmission andclient beacon reception when the switches are open, as can be seen bythe disconnected lines inside each of switches 362 a-362 n. Additionalcomponents are also possible. For example, in some embodimentsphase-shifters 364 a-364 n are included to change the phase of thefrequency when transmitting power to receiver device 370. Phase shifter364 a-364 n may transmit the power signal to receiver device 370 basedon a complex conjugate of the phase included in the encoded beaconingsignal from receiver device 370. The phase-shift may also be determinedby processing the encoded beaconing signal received from receiver device370 and identifying receiver device 370. Wireless power transmissionsystem 300 may then determine a phase-shift associated with receiverdevice 370 to transmit the power signal.

In operation, the CCB, which controls the wireless power transmissionsystem 300, receives power from a power source and is activated. The CCBthen activates the proxy antenna elements on the wireless powertransmission system and the proxy antenna elements enter a default“discovery” mode to identify available wireless receiver clients withinrange of the wireless power transmission system. For example, controllogic 310 may identify a wireless receiver client within range of thewireless power transmission system, such as client 370 by receiving anencoded beacon signal initiated by the wireless receiver client 370 atantennas 368 a-368 n. In one embodiment, when the wireless receiverclient 370 is identified (e.g., based on use a beaconing signal that isunique to that client), a set of antenna elements on the wireless powertransmission system power on, enumerate, and (optionally) calibrate forwireless power transmission. At this point, control logic 310 may alsobe able to simultaneously receive additional beaconing signals fromother wireless receiver clients at antennas 368 a-368 n.

Once the transmission configuration has been generated and instructionshave been received from control logic 310, signal generator 350generates and transfers the power waves to antenna boards 350. Based onthe instruction and generated signals, power switches 362 a-362 n areopened or closed and phase shifters 364 a-364 n are set to the phaseassociated with the transmission configuration. The power signal is thenamplified by power amplifiers 366 a-366 n and transmitted at an angledirected toward receiver device 370. As discussed herein, a set ofantennas 368 a-368 n are simultaneously receiving beacon signals fromadditional receiver clients.

FIG. 4 is a block diagram illustrating example components of a wirelesspower receiver client, in accordance with some embodiments. Asillustrated in the example of FIG. 4, the receiver 400 includes controllogic 410, battery 420, an IoT control module 425, communication block430 and associated antenna 470, power meter 440, rectifier 450, acombiner 455, beacon signal generator 460, beacon coding unit 462 and anassociated antenna 480, and switch 465 connecting the rectifier 450 orthe beacon signal generator 460 to one or more associated antennas 490a-n. Some or all of the components can be omitted in some embodiments.For example, in some embodiments, the wireless power receiver clientdoes not include its own antennas but instead utilizes and/or otherwiseshares one or more antennas (e.g., Wi-Fi antenna) of the wireless devicein which the wireless power receiver client is embedded. Moreover, insome embodiments, the wireless power receiver client may include asingle antenna that provides data transmission functionality as well aspower/data reception functionality. Additional components are alsopossible.

A combiner 455 receives and combines the received power transmissionsignals from the power transmitter in the event that the receiver 400has more than one antenna. The combiner can be any combiner or dividercircuit that is configured to achieve isolation between the output portswhile maintaining a matched condition. For example, the combiner 455 canbe a Wilkinson Power Divider circuit. The rectifier 450 receives thecombined power transmission signal from the combiner 455, if present,which is fed through the power meter 440 to the battery 420 forcharging. In other embodiments, each antenna's power path can have itsown rectifier 450 and the DC power out of the rectifiers is combinedprior to feeding the power meter 440. The power meter 440 can measurethe received power signal strength and provides the control logic 410with this measurement.

Battery 420 can include protection circuitry and/or monitoringfunctions. Additionally, the battery 420 can include one or morefeatures, including, but not limited to, current limiting, temperatureprotection, over/under voltage alerts and protection, and coulombmonitoring.

The control logic 410 can receive the battery power level from thebattery 420 itself. The control logic 410 may also transmit/receive viathe communication block 430 a data signal on a data carrier frequency,such as the base signal clock for clock synchronization. The beaconsignal generator 460 generates the beacon signal, or calibration signal,transmits the beacon signal using either the antenna 480 or 490 afterthe beacon signal is encoded.

It may be noted that, although the battery 420 is shown as charged by,and providing power to, the receiver 400, the receiver may also receiveits power directly from the rectifier 450. This may be in addition tothe rectifier 450 providing charging current to the battery 420, or inlieu of providing charging. Also, it may be noted that the use ofmultiple antennas is one example of implementation and the structure maybe reduced to one shared antenna.

In some embodiments, the control logic 410 and/or the IoT control module425 can communicate with and/or otherwise derive IoT information fromthe device in which the wireless power receiver client 400 is embedded.Although not shown, in some embodiments, the wireless power receiverclient 400 can have one or more data connections (wired or wireless)with the device in which the wireless power receiver client 400 isembedded over which IoT information can be obtained. Alternatively, oradditionally, IoT information can be determined and/or inferred by thewireless power receiver client 400, e.g., via one or more sensors. Asdiscussed above, the IoT information can include, but is not limited to,information about the capabilities of the device in which the wirelesspower receiver client is embedded, usage information of the device inwhich the wireless power receiver client is embedded, power levels ofthe battery or batteries of the device in which the wireless powerreceiver client is embedded, and/or information obtained or inferred bythe device in which the wireless power receiver client is embedded orthe wireless power receiver client itself, e.g., via sensors, etc.

In some embodiments, a client identifier (ID) module 415 stores a clientID that can uniquely identify the power receiver client in a wirelesspower delivery environment. For example, the ID can be transmitted toone or more wireless power transmission systems when communication isestablished. In some embodiments, power receiver clients may also beable to receive and identify other power receiver clients in a wirelesspower delivery environment based on the client ID.

An optional motion sensor 495 can detect motion and signal the controllogic 410 to act accordingly. For example, a device receiving power mayintegrate motion detection mechanisms such as accelerometers orequivalent mechanisms to detect motion. Once the device detects that itis in motion, it may be assumed that it is being handled by a user, andwould trigger a signal to the array to either to stop transmittingpower, or to lower the power transmitted to the device. In someembodiments, when a device is used in a moving environment like a car,train or plane, the power might only be transmitted intermittently or ata reduced level unless the device is critically low on power.

FIGS. 5A and 5B depict diagrams illustrating an example multipathwireless power delivery environment 500, according to some embodiments.The multipath wireless power delivery environment 500 includes a useroperating a wireless device 502 including one or more wireless powerreceiver clients 503. The wireless device 502 and the one or morewireless power receiver clients 503 can be wireless device 102 of FIG. 1and wireless power receiver client 103 of FIG. 1 or wireless powerreceiver client 400 of FIG. 4, respectively, although alternativeconfigurations are possible. Likewise, wireless power transmissionsystem 501 can be wireless power transmission system 101 FIG. 1 orwireless power transmission system 300 of FIG. 3, although alternativeconfigurations are possible. The multipath wireless power deliveryenvironment 500 includes reflective objects 506 and various absorptiveobjects, e.g., users, or humans, furniture, etc.

Wireless device 502 includes one or more antennas (or transceivers) thathave a radiation and reception pattern 510 in three-dimensional spaceproximate to the wireless device 102. The one or more antennas (ortransceivers) can be wholly or partially included as part of thewireless device 102 and/or the wireless power receiver client (notshown). For example, in some embodiments one or more antennas, e.g.,Wi-Fi, Bluetooth, etc. of the wireless device 502 can be utilized and/orotherwise shared for wireless power reception. As shown in the exampleof FIGS. 5A and 5B, the radiation and reception pattern 510 comprises alobe pattern with a primary lobe and multiple side lobes. Other patternsare also possible.

The wireless device 502 transmits a beacon (or calibration) signal overmultiple paths to the wireless power transmission system 501. Asdiscussed herein, the wireless device 502 transmits the beacon in thedirection of the radiation and reception pattern 510 such that thestrength of the received beacon signal by the wireless powertransmission system, e.g., RSSI, depends on the radiation and receptionpattern 510. For example, beacon signals are not transmitted where thereare nulls in the radiation and reception pattern 510 and beacon signalsare the strongest at the peaks in the radiation and reception pattern510, e.g., peak of the primary lobe. As shown in the example of FIG. 5A,the wireless device 502 transmits beacon signals over five paths P1-P5.Paths P4 and P5 are blocked by reflective and/or absorptive object 506.The wireless power transmission system 501 receives beacon signals ofincreasing strengths via paths P1-P3. The bolder lines indicate strongersignals. In some embodiments the beacon signals are directionallytransmitted in this manner to, for example, avoid unnecessary RF energyexposure to the user.

A fundamental property of antennas is that the receiving pattern(sensitivity as a function of direction) of an antenna when used forreceiving is identical to the far-field radiation pattern of the antennawhen used for transmitting. This is a consequence of the reciprocitytheorem in electromagnetics. As shown in the example of FIGS. 5A and 5B,the radiation and reception pattern 510 is a three-dimensional lobeshape. However, the radiation and reception pattern 510 can be anynumber of shapes depending on the type or types, e.g., horn antennas,simple vertical antenna, etc. used in the antenna design. For example,the radiation and reception pattern 510 can comprise various directivepatterns. Any number of different antenna radiation and receptionpatterns are possible for each of multiple client devices in a wirelesspower delivery environment.

Referring again to FIG. 5A, the wireless power transmission system 501receives the beacon (or calibration) signal via multiple paths P1-P3 atmultiple antennas or transceivers. As shown, paths P2 and P3 are directline of sight paths while path P1 is a non-line of sight path. Once thebeacon (or calibration) signal is received by the wireless powertransmission system 501, the power transmission system 501 processes thebeacon (or calibration) signal to determine one or more receivecharacteristics of the beacon signal at each of the multiple antennas.For example, among other operations, the wireless power transmissionsystem 501 can measure the phases at which the beacon signal is receivedat each of the multiple antennas or transceivers.

The wireless power transmission system 501 processes the one or morereceive characteristics of the beacon signal at each of the multipleantennas to determine or measure one or more wireless power transmitcharacteristics for each of the multiple RF transceivers based on theone or more receive characteristics of the beacon (or calibration)signal as measured at the corresponding antenna or transceiver. By wayof example and not limitation, the wireless power transmitcharacteristics can include phase settings for each antenna ortransceiver, transmission power settings, etc.

As discussed herein, the wireless power transmission system 501determines the wireless power transmit characteristics such that, oncethe antennas or transceivers are configured, the multiple antennas ortransceivers are operable to transit a wireless power signal thatmatches the client radiation and reception pattern in thethree-dimensional space proximate to the client device. FIG. 5Billustrates the wireless power transmission system 501 transmittingwireless power via paths P1-P3 to the wireless device 502.Advantageously, as discussed herein, the wireless power signal matchesthe client radiation and reception pattern 510 in the three-dimensionalspace proximate to the client device. Said another way, the wirelesspower transmission system will transmit the wireless power signals inthe direction in which the wireless power receiver has maximum gain,e.g., will receive the most wireless power. As a result, no signals aresent in directions in which the wireless power receiver cannot receiver,e.g., nulls and blockages. In some embodiments, the wireless powertransmission system 501 measures the RSSI of the received beacon signaland if the beacon is less than a threshold value, the wireless powertransmission system will not send wireless power over that path.

The three paths shown in the example of FIGS. 5A and 5B are illustratedfor simplicity, it is appreciated that any number of paths can beutilized for transmitting power to the wireless device 502 depending on,among other factors, reflective and absorptive objects in the wirelesspower delivery environment.

In retrodirective wireless power delivery environments, wireless powerreceivers generate and send beacon (or calibration) signals that arereceived by an array of antennas of a wireless power transmissionsystem. The beacon signals provide the charger with timing informationfor wireless power transfers, and also indicate directionality of theincoming signal. As discussed herein, this directionality information isemployed when transmitting in order to focus energy (e.g., power wavedelivery) on individual wireless power receiver clients. Additionally,directionality facilitates other applications such as, for example,tracking device movement.

In some embodiments, wireless power receiver clients in a wireless powerdelivery environment are tracked by a wireless power transmission systemusing a three dimensional angle of incidence of an RF signal (at anypolarity) paired with a distance determined by using an RF signalstrength or any other method. As discussed herein, an array of antennascapable of measuring phase (e.g., the wireless power transmission systemarray) can be used to detect a wavefront angle of incidence. A distanceto the wireless power receiver client can be determined based on theangle from multiple array segments. Alternatively, or additionally, thedistance to the wireless power receiver client can be determined basedon power calculations.

In some embodiments, the degree of accuracy in determining the angle ofincidence of an RF signal depends on a size of the array of antennas, anumber of antennas, a number of phase steps, method of phase detection,accuracy of distance measurement method, RF noise level in environment,etc. In some embodiments, users may be asked to agree to a privacypolicy defined by an administrator for tracking their location andmovements within the environment. Furthermore, in some embodiments, thesystem can use the location information to modify the flow ofinformation between devices and optimize the environment. Additionally,the system can track historical wireless device location information anddevelop movement pattern information, profile information, andpreference information.

FIG. 6 is a diagram illustrating an example determination of an incidentangle of a wavefront, according to some embodiments. By way of exampleand not limitation, the incident angle of a wavefront can be determinedusing an array of transducers based on, for example, the received phasemeasurements of four antennas for omnidirectional detection, or threeantennas can be used for detecting the wavefront angle on onehemisphere. In these examples, the transmitting device (i.e., thewireless device) is assumed to be on a line coming from the center ofthe three or more antennas out to infinity. If the at least threedifferent antennas are located a sufficient known distance away and arealso used to determine incident wave angle, then the convergence of thetwo lines plotted from the phase-detecting antennas is the location ofthe device. In the example of FIG. 6,

${\theta = {\sin^{- 1}\left( \frac{\lambda\Delta\phi}{2\;\pi\; s} \right)}},$

where λ is the wavelength of the transmitted signal, and Δϕ is the phaseoffset in radians and s is the inter-element spacing of the receivingantennas.

If less than one wavelength of antennas spacing is used between twoantennas, an unambiguous two-dimensional (2D) wavefront angle can bedetermined for a hemisphere. If three antennas are used, an unambiguousthree-dimensional (3D) angle can be determined for a hemisphere. In someembodiments, if a specified number of antennas, e.g., four antennas areused, an unambiguous 3D angle can be determined for a sphere. Forexample, in one implementation, 0.25 to 0.75 wavelength spacing betweenantennas can be used. However, other antenna spacing and parameters maybe used. The antennas described above are omnidirectional antennas whicheach cover all polarities. In some embodiments, in order to provideomnidirectional coverage at every polarity, more antennas may be neededdepending on the antenna type/shape/orientation.

FIG. 7 is a diagram illustrating an example minimum omnidirectionalwavefront angle detector, according to some embodiments. As discussedabove, the distance to the transmitter can be calculated based onreceived power compared to a known power (e.g., the power used totransmit), or utilizing other distance determination techniques. Thedistance to the transmitting device can be combined with an angledetermined from the above-described process to determine devicelocation. In addition, or alternatively, the distance to the transmittercan be measured by any other means, including measuring the differencein signal strength between sent and received signals, sonar, timing ofsignals, etc.

When determining angles of incidence, a number of calculations must beperformed in order to determine receiver directionality. The receiverdirectionality (e.g., the direction from which the beacon signal isreceived) can comprise a phase of the signal as measured at each ofmultiple antennas of an array. In an array with multiple hundreds, oreven thousands, or antenna elements, these calculations may becomeburdensome or take longer to compute than desirable. In order to addressreduce the burden of sampling a single beacon across multiple antennaelements and determining directionality of the wave, a method isproposed that leverages previously calculated values to simplify somereceiver sampling events.

Additionally, in some cases it is extremely beneficial to determine if areceiver within the charging environment, or some other element of theenvironment, is moving or otherwise transitory. Thus, rather than theabove attempt to determine actual or exact location, the utilization ofpre-calculated values may be employed to identify object movement withinthe environment. Each antenna unit automatically and autonomouslycalculates the phase of the incoming beacon. The Antennas (or arepresentative subset of antennas) then report the detected (or measuredphases up to the master controller for analysis). To detect movement,the master controller monitors the detected phases over time, lookingfor a variance to sample for each antenna.

Timing Acquisition Module

In embodiments now described, a Timing Acquisition Module (TAM) is usedto detect the presence of encoded beacons transmitted from wirelesspower receiver clients and/or client host devices and generate keytiming signals and triggers (e.g., Proxy GO signal,

Encoded Beacon Detect, Error Flags etc.) to a Host/CCB (computer controlboard) used by the WPTS. FIG. 8 shows and exemplary embodiment of a TAM800. In the illustrative configuration of FIG. 8, TAM 800 includes fourantennas 802 a-802 d, also labeled herein using encircled numbers ‘1’,‘2’, ‘3’, ‘4’. Each of antennas 802 a-802 d is configured to receivesignals from various devices in which wireless power receiver clientsare installed or integrated therein. In some embodiments, the data linkis implemented using Wi-Fi™ (including but not limited to IEEE 802.11a,802.11b, 802.11g, 802.11n, 802.11ac). In some embodiments, the PhysicalLayer (PHY) of an IEEE 802.11-based standard is used for TAM beaconing,without using the MAC (Media Access Channel) protocol for the802.11-based standard (rather, a custom Layer-2 protocol isimplemented).

The wireless propagation channel can be very noisy and the signaltransmitted over a wireless communication link is susceptible to fading,co-channel interference, blockage, path loss effects and multi-path.These problems may be reduced by providing spatial diversity usingmultiple antennas, which provider greater immunity to the fading,blockage and offers high quality link when compared to single a channelantenna system. Accordingly, antennas 802 a-802 d are configured toprovide such spatial diversity. Some degree of spatial diversity may beachieved location, i.e., by spacing the antennas apart. Additionalspatial diversity may be achieved by other measures, such as orientationof the antennas, or using different antennas polarization. For example,in one embodiment two of the antennas are horizontally polarized, whichthe other two antennas are vertically polarized. However, this is merelyone non-limiting example, as various antenna orientations and spacingmay also be used. In addition, more or less than four antennas may beused, depending on the particular implementation and associated factors,such as how many clients the system is to support and the wirelessmedium environment in which the system will be operating.

The signals received by the antennas are depicted as RX (receiver)signals 804. A separate signal is received from each antenna, asdepicted by RX signals 806, 808, 810, and 812. RX signals 806, 808, 810and 812 are respectively received at receivers 814, 816, 818, and 820 oftransceivers XCRV1, XCRV2, XCRV3, and XCRV4. Accordingly, RX signals806, 808, 810, and 812 are also labeled XCRVn (I, Q, RSSI), where n isthe antenna number, I and Q represent the in-phase and quadraturecomponents I(t) and Q(t) of the modulated RF signal, and RSSI is thereceived signal strength indicator, which is representative of the powerof the received RF signal. The use of RSSI is used in FIG. 8 forillustrative purposes, as each of RX signals 806, 808, 810 and 812 willhave a signal strength (an associated power level) that may (generally)vary, and the RSSI would be derived using well-known techniques byapplicable hardware, as will be recognized by those skilled in thewireless communication art.

Each of receivers 814, 816, 818, and 820 is configured to process the RXsignal it receives and output I(t) and Q(t) RF components in analogform. The I(t) and Q(t) RF components are then processed by 10 MSPS(Mega-Samples Per Second) analog-to-digital (ADC) conditioning circuitry822, which converts the analog I(t) and Q(t) RF components into digitalwaveforms. The digitized I(t) and Q(t) RF components are then receivedas input 824 by a Field Programmable Gate Array (FPGA) 826, where theyare processed, as described below.

FPGA 826 is programmed to implement various functions and algorithms,including providing communication functions with the wireless powerreceiver client devices and interacting with a host/computer controlboard (CCB) 828, which is facilitated by a host/CCB interface 830.Host/CCB interface 830 is used to send commands/data and notificationsignals between a master controller/host in the WPTS (depicted ashost/CCB 828) and the TAM via commands/data and signals received fromand sent to FPGA 826. These commands/data and signals include a GoMessage from TAM 832, a Go Message from Proxy 834, a BEACON_DETECT_IDbus 836, a BEACON_DETECT_STROBE signal 838 received from host/CCB 828,and an error signal 840 sent to host/CCB 828. In addition to thesignals/messages shown, host/CCB interface 830 may provide acommunication channel between a TAM and a host/CCB to enable varioustypes of data and messages to be exchanged between the TAM and thehost/CCB.

BEACON_DETECT_STROBE signal 838 is a single line that strobes thepresence of an encoded beacon. BEACON_DETECT_ID bus 836 is a multi-bitparallel bus used to convey binary encoded client preambles and message.In one embodiment, BEACON_DETECT_ID bus 836 is six bits wide; however,this is merely exemplary and non-limiting. Error signal 840 is used toprovide error notification interrupts in case the encoded beacon is notdetected given certain rules. An optional ACQUIRED_DIFFRENTIAL_CLOCK(not shown) may be included as a primary unit clock being regeneratedfrom a Timing Channel Pilot.

In addition to the commands/data and signals illustrated in FIG. 8,host/CCB interface 830 include various other signals/lines that are notshown. In one embodiment, these include a CCB_TAM_INT, which is adigital line from CCB to TAM for timing critical requests; aTAM_CCB_INT, which is a digital line from the TAM to CCB to notifyinterrupt and error events; a Master Out Slave In (MOSI) input to theTAM; a Master In Slave Out (MISO) output from the TAM, and a Chip/SlaveSelect signal to qualify transactions. Various clock signals may also beused, including differential digital clocks and differential RF clocks.

FPGA 826 also provides output 842 for communicating with the clientdevices. output 842 is received as digital data by a 10/100 MSPSdigital-to-analog convertor (DAC) conditioning circuitry 844. 10/100MSPS DAC conditioning circuitry 844 provides four outputs that arerespectively received by transmitters (TX) 846, 848, 850, and 852 oftransceivers XCRV1, XCRV2, XCRV3, and XCRV4. Transmitters 846, 848, 850,and 852 respectively output transmitter signals 854, 856, 858, and 860,which are received at and broadcast by antennas 802 a-802 d.

FIG. 9 illustrates further detail of the RF signal processing performedby the TAM, according to one embodiment. In this example, only thesignals for a single antenna (802 a) are depicted; however, it will beunderstood that similar components and processing would exist for eachof the other antennas 802 b, 802 c, and 802 d.

A switch 900 is configurable to pass RF signals received from antenna802 a through a wideband (WB) SAW filter 902, a narrowband (NB) SAWfilter 904, or a pass-through 906. Alternatively, a wideband ornarrowband SAW filter can be used without switching, or no SAW filter isused. A balun 908 (balanced to unbalanced) is used to couple thesingle-ended RF signal to a double-ended signal that is received as aninput by a transceiver chip 910.

In the illustrated embodiment, transceiver chip is an IEEE 802.11g/b RFtransceiver chip. Alternatively, RF transceiver chips that support otherIEEE 802.11 standards (alone or in combination) may be used, includingone or more of 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac standards.IEEE 802.11 transceiver chips are available from various vendors,including Maxim, Cypress Semiconductor, Marvell, and Texas Instruments(as well as others). In one embodiment, IEEE 802.11g/b RF transceiverchip 910 is a Maxim series 2830 RF transceiver chip. Since this Maximchip provides on-chip monolithic filters for both the receiver andtransmitter, it may be used without a SAW filter. In some embodiments,only the PHY of a IEEE 802.11 transceiver chip is used for somepurposes, such as beaconing. (It is noted that some IEEE 802.11transceiver chips provide both PHY and MAC layer circuitry andassociated functionality, while other IEEE 802.11 transceiver chips,such as the Maxim series 2830 RF transceiver chip, only provide PHYlayer circuitry.)

10 MSPS ADC Conditioning Circuitry 822 may be generally implementedusing a 10 MSPS ADC chip available from various vendors. Such chips willalso include appropriate signal conditioning circuitry. In oneembodiment, a Linear Technology 12 or 14 bit 10 MSPS ADC chip is used.It is further noted that use of a 10 MSPS ADC is merely exemplary, asother sampling rates, including higher sampling rates, may also be used.

TAM and WPTS Encoded Beacons

In some embodiments, encoded beacons are transmitted by wireless powerreceiver clients to identify the wireless power receiver clients withthe TAM and/or WPTS. A WPTS may also broadcast signals and/or messagesthat are encoded to enable the signals and/or messages to be targeted tospecific wireless power receiver clients. Under implementations in whichencoded beacons are used to communication with the TAM and (separately)the WPTS, the encoded beacons for the same client may use the same codesin some embodiments, or different codes in other embodiments. Inaddition, the beacons used by a client to beacon to the WPST and tobeacon to the TAM may use different RF radio bands and/or channels.

In the case of an IEEE 802.11 implementation, a center frequency of 2.4GHz (802.11b/g/n/ax) or 5 GHz (802.11a/h/j/n/ac/ax) is usually be used(noting there are IEEE 802.11 standards defining use of other centerfrequencies). Using the Nyquist rate, at a 1 MBPS encoded beacon rate,the minimum sampling frequency is 2 MSPS. The use of componentssupporting higher sampling rates (e.g., 10 MSPS DACs) improves theacquisition processing in the presence of pulse shaping. In oneembodiment, the encoded beacon code length is settable to 16, 32, and 64bits. In another embodiment, encoded beacon code lengths of 128 bits aresupported.

Generally, various types of codes may be used; however it is preferableto use codes that are more detectable, particularly in harsh RFenvironments. In one embodiment, the encoded beacon codes are builtusing Barker codes, which are codes that are known for theirdetectability and cross-correlation properties. For example, any of a16-bit, 32-bit, 64-bit, or 128-bit code could be built using acombination of Barker codes that are concatenated. Other codes may bebuild using Barker code sequences interspersed with non-Barker codesequences. A listing of some known Barker codes is shown in TABLE 1below.

TABLE 1 Length Codes Sidelobe level ratio 2 +1 −1 +1 +1   −6 dB 3 +1 +1−1  −9.5 dB 4 +1 +1 −1 +1 +1 +1 +1 −1   −12 dB 5 +1 +1 +1 −1 +1   −14 dB7 +1 +1 +1 −1 −1 +1 −1 −16.9 dB 11 +1 +1 +1 −1 −1 −1 +1 −1 −1 +1 −1−20.8 dB 13 +1 +1 +1 +1 +1 −1 −1 +1 +1 −1 +1 −1 +1 −22.3 dB

FIG. 10 shows a flowchart 1000 illustrating operations for establishingcommunication with a wireless power receiver client or host device andproviding a code to be used by the client/device when broadcasting itsencoded beacon. In a block 1002, a signal transmitted from a wirelesspower receiver client or host device is received at multiple of the TAMantennas. At this point, communication with the client/device has notbeen established; however, characteristics of the signals, such assignal strength, may be detected. Accordingly, in a block 1004 thesignal is processed is processed using the RF receiver circuitryassociated with each TAM antenna/channel, and the RSSI of the signal asreceived at each TAM antenna is obtained. In embodiments using an IEEE802.11 transceiver chip that supports RSSI measurement, the RSSI can beobtained from an interface on the chip. Alternative, RSSI can bemeasured using any of various well-known schemes.

In a block 1006, the antenna/channel with the greatest RSSI is selectedto be used for communication with the client or device. As shown by thedotted loop back to block 1002, the operations of blocks 1002, 1004, and1006 may be periodically repeated to ensure the best communicationchannel is being used to communicate with the client/device. Forexample, since most of the devices expected to be powered by a WPTS aremobile devices, the location of such devices may change as a user (withthe device) moves about within the charging range of a WPTS.

Once the antenna/channel is selected in block 1006, a communicationsession with the wireless power receiver client or host device isestablished in a block 1008. Establishment of a communication channelmay be performed using various well-known schemes and/or protocols. Forexample, if the communication is with a wireless power receiver clientchip or module, a standardized IEEE 802.11 protocol may be used in someembodiments, while other embodiments may use a proprietary protocolsupported by both the wireless power receiver client and the TAM.

Once communication with the wireless power receiver client or hostdevice is established, the beacon code to be used the wireless powerreceiver client for the TAM beacon is either assigned to the wirelesspower receiver client or obtained from the wireless power receiverclient. In one embodiment using a wireless power receiver client chip ormodule, a TAM beacon code is pre-assigned to the chip/module, somewhatakin to a MAC address. As with MAC addresses, the TAM beacon code shouldbe unique, such that no two wireless power receiver client chips/moduleshave the same TAM beacon code.

WPTS Tile with TAM

In some embodiments, the WPTS and TAM facilities are combined orotherwise integrated in a single component, referred to herein as a“tile.” In one exemplary implementation of the WPTS tile, the tile isconfigured to replace a ceiling tile in the false ceiling of an officebuilding, business, or other structure, hence the name “tile.” Moreover,it is envisioned that multiple tiles will be used in some locations in acoordinated manner to provide WPTS coverage to large areas.

FIG. 11 shows an exemplary embodiment of a WPTS tile 1100, whichincludes a WPTS 300A and a TAM 800A. WPTS 300A has a configurationsimilar to WPTS 300 illustrated in FIG. 3 and discussed above. TAM 800Ahas a configuration similar to TAM 800 of FIG. 8, combined with aspectsof the circuitry of FIG. 9. For example, TAM 800A includes four antennas802 a-802 d, each coupled to a respective set of RF circuitry similar tothat shown in FIG. 9, depicted as Balun/RF Filter blocks 1102. In theillustrated embodiment, four 802.11g/b RF transceiver chips 910 areused, each coupled to a respective Balun/RF Filter block 1102.Optionally, two 802.11g/b RF transceiver chips configured to supportantenna diversity using two antennas may be used. The remainingcircuitry, including 10 MSPS ADC conditioning circuitry 822, FPGA 826,and 10/100 MSPS DAC conditioning circuitry 844 is the same as shown inTAM 800, and functions in a similar manner to that discussed above.

TAM 800A may further include an external data interface 1104, which isconfigured to facilitate communication with external components orsystems. For example, external data interface 1104 may be a wirelessinterface such as an 802.11 Wi-Fi™ interface that enables TAM 800A tocommunication with other components or systems over a WLAN. Optionally,external data interface 1104 may be a wired interface, such as anEthernet interface. In some embodiments, TAM 800A performs somecommunication with WPTS 300A using a wireless or wired out-of-bandcommunication channel (not shown) using external data interfaces 1104and 315. (“Out-of-band” is used to distinguish this communicationchannel from communication over host/CBB interface 830, which is anin-band communication channel.)

During operation of WPTS tile 1100, most WPTS operations are performedby WPTS 300A in a similar manner to that described above, includingreceiving beacons from wireless power receiver clients and transmittingwireless power signals to wireless power receiver clients using theantenna array board 350. However, rather than use a predeterminedschedule for providing power signals to wireless power receiver clients(and in conjunction having the wireless power receiver clients performbeaconing in accordance with the predetermined schedule), power ondemand is supported, whereby wireless power receiver clients mayasynchronously request power and have those requests serviced by theWPTS by transmitting wireless power signals to the clients. Also, ratherthan receiving the requests for power using WPTS 300A, the requests inthe form of encoded beacons transmitted from wireless power receiverclients are received and processed by TAM 800A, which extracts client IDinformation from encoded beacons and forward the client ID informationin the form of a BEACON_DETECT_ID over Host/CCB interface 830. TheBEACON_DETECT_ID is used by WPTS 300A to identify the wireless powerreceiver client requesting power, broadcast information to instruct orotherwise cause the wireless power receiver client to transmit a WPTSbeacon, and using the WPTS beacon to adjust the phases of the wirelesspower receiver clients to direct wireless power transmission signalstoward the beaconing wireless power receiver client.

Prior to performing the foregoing, various communications between theWPTS, TAM, and wireless power receiver clients are first established,and various configuration information is exchanged. FIG. 12 shows aflowchart 1200 illustrating operations performed to establishcommunication between a WPTS and a wireless power receiver client andassociated configuration operations, according to one embodiment. Asdiscussed, in some embodiments, the wireless power transmission systemmay be used for wireless communication transmission waves, wirelesspower transmission waves, or dual-purpose data/power transmission waves.

The process begins in a block 1202 in which a wireless power receiverclient move into the charging range of a WPTS, and detects presence ofthe WPTS. Detection or the WPTS can be performed using various means,such as a periodic beacon broadcast by the WPTS (for the purpose ofadvertising its presence). The wireless power receiver client may alsodetermine that the signal strength of wireless power transmission systemis above a signal strength range and therefore, that wireless powerreceiver client is within the charging range of wireless powertransmission system 101.

In response to detecting it has moved into a WPTS charging range, thewireless power receiver client broadcasts a beacon of signal to initiatea handshake process that is used to establish communication with theWPTS, as depicted in a block 1204. In some embodiments, the wirelesspower receiver client will be preprogrammed to broadcast an encodedbeacon and the WPTS will be configured to detect the encoded beacon. Inother embodiments, a predetermined beacon format will be used for allwireless power receiver clients to initiate the handshake process.

In a block 1206, a communication link between the WPTS and wirelesspower receiver client is established. For example, if an encoded channelis to be used for communication between the WPTS and wireless powerreceiver client, a key exchange or the like may be employed to establishthe keys for encoding communications of the encoded channel. In caseswhere the WPTS is configured to receive encoded beacons and/or signalsfrom (previous) unknown wireless power receiver clients, thecommunication may be established without a key exchange.

In an optional block 1208, the WPTS obtains client-specific informationfrom the wireless power receiver client. In some embodiments, the WPTSprocesses the encoded beacon signal received from the wireless powerreceiver client to identify client-specific information associated withthe wireless power receiver client. In this manner, beacon signals fromindividual wireless power receiver clients can be identified.

Client-specific information may include various properties and/orrequirements corresponding to a wireless power receiver client. Forexample, the client-specific information may include, but is not limitedto, battery level of wireless power receiver client host device, batteryusage information, temperature information, estimated distance to theWPTS, and information identifying other nearby wireless powertransmission systems, currently providing power to wireless powerreceiver client, etc.

In some embodiments, initial data exchange between a WPTS and wirelesspower receiver client will be unencoded or otherwise use an encodedchannel that is not specific to an individual client. Accordingly, in anoptional block 1210 the WPTS assigns a beacon code to be used by thewireless power receiver client for future beaconing and/or to be used bythe WPTS to convey a message or request to the wireless power receiverclient. For example, in some embodiments a WPTS will broadcast a beaconthat is encoded such that only a particular wireless power receiverclient can decode and/or detect it. This is described in further detailbelow. In other embodiments, the wireless power receiver client willhave a pre-programmed code that is provided to the WPTS in block 1210,or optionally is provided to the WPTS in block 1208 as part of the WPTSobtaining client-specific information.

As described above, in some embodiments multiple wireless powertransmission systems are used in a cooperative manner to provide largercharging coverage areas. Accordingly, in an optional block 1212,wireless power receiver client ID's and client-specific information isexchanged with one or more other WPTS. In some embodiments, when a newclient is detected by a given WPTS, the operations of blocks 1204, 1206,1208, and 1210 will be performed, and the WPTS will communicate theclient ID and client-specific information with one or more other WPTS inblock 1212. Optionally, or in addition to, client ID's andclient-specific information may be periodically exchanged.

In one embodiment, WPTS will maintain a management information base(MIB) or the like, which is distributed across all WPTS's in an overallsystem, and in which client ID's and associated client-specificinformation is stored for currently-active wireless power receiverclients. Optionally, the MIB may store client ID's and client-specificinformation for previous clients that are currently inactive. Under theMIB approach, when a currently-active client moves into the chargingrange of a second WPTS, rather than repeat the operations of block 1208and/or 1210, the second WPTS can lookup the client-specific informationand obtain the WPTS beacon that has already been assigned in its MIB.

Generally, the beacon signals may be encoded or modulated with atransmission configuration that is provided to selected clients in thewireless power delivery environment. The transmission configuration maybe coherent signals determined by computing the complex conjugate of areceived beacon (or calibration) signal at each antenna of the arraysuch that the coherent signal is phased for delivering power. In someembodiments, a different transmission configuration is provided to eachclient or communication path. Different transmission configurations foreach of multiple wireless power receiver clients within the chargingrange of a WPTS can facilitate simultaneous or near simultaneoustransmission of beacon signaling by the clients in the wireless powerdelivery environment, while further ensuring that only authorized(selected) clients are “locked” by the wireless power delivery system.

FIG. 13 shows a message flow diagram 1300 illustrating messages that areexchanged between a WPTS and a TAM during initialization of a WPTS tile,according to one embodiment. As depicted by a message exchange 1302, theWPTS and TAM establish a communication channel over either the host/CCBinterface or using an out-of-band channel. As discussed above, examplesof out-of-band channels include a wireless WLAN link, such as a Wi-Fi™link, and a wired network link, such as an Ethernet link.

As depicted by a message 1302, the WPTS issues a GO MESSAGE FROM PROXYto the TAM. This message includes some coarse timing information. TheTAM then performs some timing configuration and system initializationoperations using the information in the GO MESSAGE FROM PROXY message,as depicted in a block 1304. Upon completion, the TAM returns a GOMESSAGE FROM TAM 1306 including finer timing information.

Either following the GO MESSAGE FROM TAM 1306 (as shown) or sometimeprior thereto, the WPTS may send client ID's and optional codes 1308 tothe TAM, as depicted by a message 1310. If both the WPTS and TAM areinitialized at the same time, the WPTS will not have any clients, andthus may have no client ID's to send to the TAM. Optionally, under theforegoing MIB scheme, when a new WPTS is joined to a currently operatingsystem including multiple WPTS, the new WPTS may obtain a copy of theMIB during initialization, and pass that information to the TAM. As yetanother option, the MIB could be in shared memory that is accessible toboth the WPTS and the TAM, enabling the TAM to access the client ID datawithout it being forwarded in one or more messages.

The wireless power receiver client ID information is used by the TAM toassociate those client IDs with the wireless power receiver clients whenthe TAM is communicating with those wireless power receiver clients. Inparticular, when the BEACON_DETECT_ID in connection with a power requestfrom a given wireless power receiver client will correspond to theclient ID that was sent to the TAM with message 1310.

When the optional codes are included with message 1310, those codes maybe used by the TAM for the encoded TAM beacon codes to be assigned tothe wireless power receiver clients. In one embodiment, during theoperations of flowchart 1200, the WPTS provides the codes to be used bythe wireless power receiver client for beaconing to the WPTS, andbeaconing to the TAM. As discussed above, under some embodiments thatsame beacon may be used (for both the WPTS and TAM), while for otherembodiments separate beacons are used.

FIG. 14 shows a message/signal flow diagram 1400 illustrating operationsand message flows associated with implementation of a wireless power-ondemand scheme, according to one embodiment. As depicted by messageexchange 1402, the TAM and wireless power receiver client will haveestablished communication, such as using the operations of flowchart1000 shown in FIG. 10 and discussed above. At this point, the WPTS isconfigured to service power-on demand requests from the wireless powerreceiver client.

The request/service sequence begins with the wireless power receiverclient broadcasting its encoded TAM beacon, as depicted by signal 1404.As depicted in a block 1406, the TAM will detect the encoded TAM beaconand identify the wireless power receiver client beaconing the encodedTAM beacon by decoding the beacon and looking up which wireless powerreceiver client is associated with the particular encoding.

Next, the TAM will place the BEACON_DETECT_ID bits corresponding to thewireless power receiver client ID on the BEACON_DETECT_ID bus 836 andactivate the BEACON_DETECT_STROBE 838, as depicted by signal 1408. TheBEACON_DETECT_STROBE is used to notify the WPTS that a client isrequesting power, and the BEACON_DETECT_ID is used to identify theparticular client.

At this point, the WPTS prepares to service the wireless power requestfor the client. There are various ways this may be accomplished,ultimately concluding with the WPTS antenna array being configured tosend wireless power signals to the requesting client in the mannerdescribed above. Under some embodiments, the antenna array may beconfigured to automatically direct wireless power signals to a clientbased on signals received from the client, such as a beacon. Moreover,under some embodiments the directing of the wireless power signals isperformed based on the beacon signal itself (i.e., the phase of the RFsignal as received at the different antennas in the array), without useof any information encoded in the beacon. In other embodiments, thebeacon is encoded and the coding is used to identify the particularclient or for extracting characteristics of the beacon signal broadcastby the client. Knowledge of the client may be used for one or more ofassisting in directing the wireless power signals to the client andtailoring the delivery of power to the client based on theclient-specific information the WPTS previously acquired for the client.

Returning to FIG. 14, in some embodiments the WPTS broadcasts an ALLQUIET beacon to be received by any wireless power receiver client withinits charging area. In some embodiments, one or more other WPTS may alsobroadcast an ALL QUIET beacon, such as under situations where thewireless power receiver client requesting power is within the chargingrange of multiple WPTS. The ALL QUIET beacon instructs the wirelesspower receiver clients not to beacon for a predetermined period of time(either beacon a WPTS beacon and/or TAM beacon). In connection with theALL QUIET beacon, the WPTS broadcast a signal 1412 comprising a commandinstructing the wireless power receiver client requesting power tobeacon its WPTS beacon. Generally, signal 1412 may be encoded such thatit is decoded (and subsequently processed) only by the wireless powerreceiver client requesting power; when signal 1412 is received by anyother wireless power receiver clients within the broadcast range of theWPTS, it is one or more of not detected or ignored.

In some embodiments the ALL QUIET signal 1410 and signal 1412 may becombined into a single WPTS beacon. Under this scenario, the beacon isreceived an processed by any wireless power receiver clients within thebroadcast range of the WPTS, with all but the power requesting wirelesspower receiver client interpreting the beacon as a command to be quiet,while the power requesting wireless power receiver client interprets thebeacon as command to broadcast its WPTS beacon.

In response to receiving signal 1412 (or the foregoing combined WPTSbeacon), the wireless power receiver client request power broadcasts itsWPTS beacon, as depicted by a signal 1414. As discussed above, the WPTScan detect phases in beacons received from wireless power receiverclients and direct wireless power signals towards those clients. Usingthis means, wireless power is delivered to service the wireless powerreceiver client power request, as depicted by a signal 1416. If thewireless power receiver client broadcasts an encoded WPTS beacon, theWPTS can decode the beacon to identify the wireless power receiverclient and deliver power to the WPTS, potentially tailored toclient-specific information for the wireless power receiver client.

In some embodiments, a wireless power receiver client will broadcast itsencoded TAM beacon signal when it determines that its host device has alow battery level. For example, the wireless power receiver client mayremain in sleep mode until it determines that the power level is below athreshold value. Wireless power receiver client may then wakeup andinitiate the wireless power transmission sequence by broadcasting itsencoded TAM beacon.

In other embodiments, a wireless power receiver client may broadcast itencoded TAM beacon signal in response to detecting it has moved withinthe charging range of a WPTS. For example, a wireless power receiverclient may determine to initiate the wireless power transmissionsequence by determining that the signal strength of signals receivedfrom a WPTS is above a signal strength range and therefore, that theuser (of the wireless power receiver client host device) has roamed intothe wireless power charging range of the WPTS.

FIG. 15 shows a wireless power delivery environment 1500 including twoWPTS tiles 1100-1 and 1100-2, each configured in a similar manner toWPTS tile 1100 of FIG. 11 discussed above. WPTS tiles 1100-1 and 1100-2are coupled in communication via a link 1502, which generally may be awireless link (e.g., Wi-Fi™) or a wired link (e.g., Ethernet), althoughproprietary links may also be used. Each of WPTS tiles 1100-1 and 1100-2also include a local instance of a management information base (MIB)1504.

Each of WPTS tiles 1100-1 and 1100-2 has a respective charging range, asdepicted by the arcs labeled TILE 1 RANGE and TILE 2 RANGE. Wirelessdevice 102 a including wireless power receiver client 103 a is withinthe charging range of WPTS tile 1100-1, and wireless device 102 nincluding wireless power receiver client 103 n is within the chargingrange of WPTS tile 1100-2, while wireless device 102 b including awireless power receiver client 103 b is within the charging range ofboth WPTS tile 1100-1 and WPTS tile 1100-2.

Wireless power receiver client 103 a is configured to receive wirelesspower signals from WPTS tile 1100-1, as depicted by a WPTS signalpath/link 1506, which may also support data communication betweenWireless power receiver client 103 a and the WPTS of WPTS tile 1100-1.Wireless power receiver client 103 a is also configured to communicatewith the TAM of WPTS tile 1110-1, as depicted by a TAM link 1508, whichmay also be used for data communication between Wireless power receiverclient 103 a and the TAM. Similarly, client 103 b is configured toreceive wireless power signals from WPTS tile 1100-1 via a WPTS signalpath/link 1510, and is also configured to communicate with the TAM ofWPTS tile 1110-2 via a TAM link 1512.

As mentioned, wireless device 102 b and wireless power receiver client103 b is within the charging range of both WPTS tiles 1100-1 and 1100-2.Under an aspect of the distributed management scheme, one WPTS tile isselected to communicate with a wireless power receiver client 103 b at atime. In the example illustrated in FIG. 15, that WPTS tile for wirelesspower receiver client 103 b is WPTS tile 1100-2, as depicted by a WPTSsignal path/link 1514. In addition, TAM operations for wireless powerreceiver client 103 b are performed by the TAM in WPTS tile 1100-2, asdepicted by a TAM link 1516.

In some embodiments, multiple TAMs on different WPTS tiles mayconcurrently be in communication with a given wireless power receiverclient, as depicted by optional TAM link 1518. For example, thisapproach could be used to manage “handoff” of WPTS operations as awireless power receiver client moves within overlapping charging rangesof WPTS tiles. In some embodiments, similar operations may be performedusing WPTS data links (not shown), which would be used to enableconcurrent communication with a wireless power receiver client by theWPTS in two or more WPTS tiles. However, as noted above, only one WPTSwill provide power to a wireless power receiver client at any givenpoint in time.

In some embodiments, the MIB 1504 instances are used to coordinatedelivery of power to wireless power receiver clients as they roam withinan environment with multiple WPTS tiles. For example, under one approacheach WPTS tile has a local instance of an MIB containing informationrelating to all of the wireless power receiver clients currently beingoperated within the environment (as of a last distributed update).Updates to the distributed MIB may be performed periodically or inresponse to detected changes for a given WPTS tile. For example, WPTStiles with overlapping ranges may periodically exchange MIB data, eitherexchanging their entire MIB data or using a delta scheme (e.g., changesince the last period). Under an alternative approach, changes to theMIB data for local instances are propagated as wireless power receiverclients move within the overall environment, while observing that WPTStiles with charging ranges that are not proximate to the location of agiven wireless power receiver client that has recently moved may nothave their MIB instances updated to reflect the move.

Through use of the local MIB instances, the overall system cancoordinate which WPTS tile is currently providing power to each wirelesspower receiver client, as well as facilitate handover between the WPTStiles. Also, coordinated operation of multiple WPTS tiles (typicallytwo) having overlapping charging ranges in which a given wireless powerreceiver client is present may be performed. For example, consider theuse of the ALL QUIET beacon or signal. When a given WPTS tile broadcastsan ALL QUIET beacon or signal in connection with providing power to awireless power receiver client within the charging range of another WPTStiles (i.e., the wireless power receiver client is within theoverlapping charging ranges of the two WPTS tiles), the two WPTS tilescan be coordinated such that each tile issues an ALL QUIET beacon. Inthis manner, any other wireless power receiver clients within theoverlapping charging range will be instructed not to beacon, and thusnot cause RF interference with the WPTS beacon broadcast by the wirelesspower receiver client making the power request.

Although some embodiments have been described in reference to particularimplementations, other implementations are possible according to someembodiments. Additionally, the arrangement and/or order of elements orother features illustrated in the drawings and/or described herein neednot be arranged in the particular way illustrated and described. Manyother arrangements are possible according to some embodiments.

In each system shown in a figure, the elements in some cases may eachhave a same reference number or a different reference number to suggestthat the elements represented could be different and/or similar.However, an element may be flexible enough to have differentimplementations and work with some or all of the systems shown ordescribed herein. The various elements shown in the figures may be thesame or different. Which one is referred to as a first element and whichis called a second element is arbitrary.

In the description and claims, the terms “coupled” and “connected,”along with their derivatives, may be used. It should be understood thatthese terms are not intended as synonyms for each other. Rather, inparticular embodiments, “connected” may be used to indicate that two ormore elements are in direct physical or electrical contact with eachother. “Coupled” may mean that two or more elements are in directphysical or electrical contact. However, “coupled” may also mean thattwo or more elements are not in direct contact with each other, but yetstill co-operate or interact with each other. Additionally,“communicatively coupled” means that two or more elements that may ormay not be in direct contact with each other, are enabled to communicatewith each other. For example, if component A is connected to componentB, which in turn is connected to component C, component A may becommunicatively coupled to component C using component B as anintermediary component.

An embodiment is an implementation or example of the inventions.Reference in the specification to “an embodiment,” “one embodiment,”“some embodiments,” or “other embodiments” means that a particularfeature, structure, or characteristic described in connection with theembodiments is included in at least some embodiments, but notnecessarily all embodiments, of the inventions. The various appearances“an embodiment,” “one embodiment,” or “some embodiments” are notnecessarily all referring to the same embodiments.

Not all components, features, structures, characteristics, etc.described and illustrated herein need be included in a particularembodiment or embodiments. If the specification states a component,feature, structure, or characteristic “may”, “might”, “can” or “could”be included, for example, that particular component, feature, structure,or characteristic is not required to be included. If the specificationor claim refers to “a” or “an” element, that does not mean there is onlyone of the element. If the specification or claims refer to “anadditional” element, that does not preclude there being more than one ofthe additional element.

An algorithm is here, and generally, considered to be a self-consistentsequence of acts or operations leading to a desired result. Theseinclude physical manipulations of physical quantities. Usually, thoughnot necessarily, these quantities take the form of electrical ormagnetic signals capable of being stored, transferred, combined,compared, and otherwise manipulated. It has proven convenient at times,principally for reasons of common usage, to refer to these signals asbits, values, elements, symbols, characters, terms, numbers or the like.It should be understood, however, that all of these and similar termsare to be associated with the appropriate physical quantities and aremerely convenient labels applied to these quantities.

As discussed above, various aspects of the embodiments herein may befacilitated by corresponding software and/or firmware components andapplications, such as software and/or firmware executed by an embeddedprocessor or the like. Thus, embodiments of this invention may be usedas or to support a software program, software modules, firmware, and/ordistributed software executed upon some form of processor, processingcore or embedded logic a virtual machine running on a processor or coreor otherwise implemented or realized upon or within a non-transitorycomputer-readable or machine-readable storage medium. A non-transitorycomputer-readable or machine-readable storage medium includes anymechanism for storing or transmitting information in a form readable bya machine (e.g., a computer). For example, a non-transitorycomputer-readable or machine-readable storage medium includes anymechanism that provides (i.e., stores and/or transmits) information in aform accessible by a computer or computing machine (e.g., computingdevice, electronic system, etc.), such as recordable/non-recordablemedia (e.g., read only memory (ROM), random access memory (RAM),magnetic disk storage media, optical storage media, flash memorydevices, etc.). The content may be directly executable (“object” or“executable” form), source code, or difference code (“delta” or “patch”code). A non-transitory computer-readable or machine-readable storagemedium may also include a storage or database from which content can bedownloaded. The non-transitory computer-readable or machine-readablestorage medium may also include a device or product having contentstored thereon at a time of sale or delivery. Thus, delivering a devicewith stored content, or offering content for download over acommunication medium may be understood as providing an article ofmanufacture comprising a non-transitory computer-readable ormachine-readable storage medium with such content described herein.

The operations and functions performed by various components describedherein may be implemented, at least in part, by software running on aprocessing element, via embedded hardware or the like, or anycombination of hardware and software. Such components may be implementedas software modules, hardware modules, special-purpose hardware (e.g.,application specific hardware, ASICs, DSPs, etc.), embedded controllers,hardwired circuitry, hardware logic, etc. Software content (e.g., data,instructions, configuration information, etc.) may be provided via anarticle of manufacture including non-transitory computer-readable ormachine-readable storage medium, which provides content that representsinstructions that can be executed. The content may result in a computerperforming various functions/operations described herein.

As used herein, a list of items joined by the term “at least one of” canmean any combination of the listed terms. For example, the phrase “atleast one of A, B or C” can mean A; B; C; A and B; A and C; B and C; orA, B and C.

The above description of illustrated embodiments of the invention,including what is described in the Abstract, is not intended to beexhaustive or to limit the invention to the precise forms disclosed.While specific embodiments of, and examples for, the invention aredescribed herein for illustrative purposes, various equivalentmodifications are possible within the scope of the invention, as thoseskilled in the relevant art will recognize.

These modifications can be made to the invention in light of the abovedetailed description. The terms used in the following claims should notbe construed to limit the invention to the specific embodimentsdisclosed in the specification and the drawings. Rather, the scope ofthe invention is to be determined entirely by the following claims,which are to be construed in accordance with established doctrines ofclaim interpretation.

What is claimed is:
 1. A method, comprising: receiving, by a timingacquisition module (TAM) of a wireless power transmission system (WPTS)via at least one group of antennas of the TAM, an encoded beaconbroadcast of an encoded beacon from a wireless power receiver device ofone or more wireless power receiver devices indicating that the wirelesspower receiver device has requested power via a power request; inresponse to extracting, by the TAM from the encoded beacon, anidentification of the wireless power receiver device, notifying, by theTAM, a controller of the WPTS of the power request comprisingreferencing the identification of the wireless power receiver device andindicating that the wireless power receiver device has requested thepower; and in response to the notifying, transmitting, using the atleast one group of antennas of the WPTS, wireless power signals to thewireless power receiver device to facilitate servicing of the powerrequest.
 2. The method of claim 1, wherein the WPTS uses the at leastone group of antennas of the WPTS to receive signals from the one ormore wireless power receiver devices.
 3. The method of claim 2, whereinthe encoded beacon has been broadcast using a signal defined by anInstitute of Electrical and Electronics Engineers 802.11 based standard.4. The method of claim 2, wherein the signals are first signals, andfurther comprising: receiving, by the TAM, second signals transmittedfrom the one or more wireless power receiver devices at one or moreantennas of the at least one group of antennas of the TAM; determining,by the TAM for the wireless power receiver device, an antenna of the oneor more antennas of the at least one group of antennas of the TAM thatis receiving a second signal of the second signals having a signalstrength that is higher than respective signal strengths of remainingsecond signals of the second signals other than the second signal; andusing a channel associated with the antenna of the at least one group ofantennas of the TAM to communicate with the wireless power receiverdevice.
 5. The method of claim 1, wherein the TAM is a first TAM,wherein the WPTS is a first WPTS including the first TAM, wherein thefirst TAM comprises a first charging range that is operating in avicinity of a second WPTS, wherein the second WPTS comprises a secondTAM that comprises a second charging range that comprises a portionoverlapping the first charging range, and wherein the method furthercomprises: detecting, via the first WPTS, that the wireless powerreceiver device is within the first and second charging ranges; andbased on a defined criterion, coordinating, via the first WPTS with thesecond WPTS, to determine which of at least one of the first WPTS or thesecond WPTS is to transmit power signals to the wireless power receiverdevice.
 6. The method of claim 1, wherein the encoded beacon has beenencoded with a code comprising a Barker code sequence.
 7. The method ofclaim 1, further comprising: receiving, by the WPTS, a WPTS beaconbroadcast by the wireless power receiver device, wherein the WPTS beaconfacilitates the wireless power receiver device receiving the wirelesspower signals from the WPTS, and wherein the encoded beacon is a firstencoded beacon; and broadcasting, by the WPTS, a second encoded beaconor a signal comprising a command directing the wireless power receiverdevice to broadcast the WPTS beacon.
 8. The method of claim 7, whereinthe signal is a first signal, and wherein the method further comprises:broadcasting, by the WPTS, a beacon or a second signal comprising acommand instructing wireless power receiver devices of the one or morewireless power receiver devices that have received the beacon or thesecond signal to withhold from transmitting any beacon for a definedamount of time.
 9. The method of claim 1, further comprising: assigning,by the WPTS, respective unique codes to the one or more wireless powerdevices.
 10. The method of claim 1, wherein the respective unique codeshave been programmed into respective memory devices of the one or morewireless power receivers devices as pre-programmed codes, and whereinthe method further comprises: receiving, by the WPTS, the pre-programmedcodes, wherein the transmitting of the wireless power signals comprisestransmitting, based on a pre-programmed code of the pre-programmedcodes, the wireless power signals to the wireless power receiver deviceto facilitate the servicing of the power request.
 11. The method ofclaim 1, further comprising: based on the encoded beacon, determining,by the WPTS, client-specific information corresponding to the wirelesspower receiver device comprising at least one of a battery level of thewireless power receiver device, temperature information corresponding tothe wireless power receiver device, an estimated distance between thewireless power receiver device and the WPTS, or information representinganother WPTS, other than the WPTS, that has been providing power to thewireless power receiver device.
 12. The method of claim 1, furthercomprising: based on the encoded beacon, modifying, by the WPTS, a phaseof a transmission of a wireless power signal of the wireless powersignals.
 13. A system, comprising: a processor; and a memory that storesexecutable instructions that, when executed by the processor, facilitateperformance of operations, the operations comprising: receiving, by atiming acquisition module (TAM) of the system via at least one group ofantennas of the TAM, a broadcast from a wireless power receiver device,wherein the broadcast comprises an encoded beacon representing that thewireless power receiver device has requested power; in response toextracting, by the TAM, an identification of the wireless power receiverdevice from the encoded beacon, communicating, by the TAM, anotification to a subsystem of the system that references theidentification of the wireless power receiver device and that indicatesthat the wireless power receiver device has requested power; and basedon the identification of the wireless power receiver device,transmitting, using the at least one group of antennas, wireless powersignals to the wireless power receiver device.
 14. The system of claim13, wherein the operations further comprise: receiving, using the atleast one group of antennas, beacons from respective wireless powerreceiver devices comprising the wireless power receiver device.
 15. Thesystem of claim 13, wherein the operations further comprise: receivingsignals transmitted from respective wireless power receiver devicescomprising the wireless power receiver device at one or more antennas ofthe at least one group of antennas of the TAM; determining, for thewireless power receiver device, an antenna of the one or more antennasthat has received a signal of the signals having a signal strength thatis higher than respective signal strengths of other signals of thesignals other than the signal; and using a channel associated with theantenna to communicate with the wireless power receiver device.
 16. Thesystem of claim 13, wherein the operations further comprise: receiving abroadcast system beacon from the wireless power receiver device tofacilitate the wireless power receiver device being able to receive thewireless power signals via the subsystem, wherein the encoded beacon isa first encoded beacon; and broadcasting, using the subsystem, a secondencoded beacon or a signal comprising a command directing the wirelesspower receiver device to broadcast the system beacon.
 17. The system ofclaim 16, wherein the signal is a first signal, and wherein theoperations further comprise: broadcasting, using the subsystem, a beaconor a second signal comprising a command instructing wireless powerreceiver devices of respective wireless power receiver devices that havereceived the beacon or the second signal to withhold from transmittingany beacon for a predetermined amount of time, wherein the respectivewireless power receiver devices comprise the wireless power receiverdevice.
 18. The system of claim 13, wherein the operations furthercomprise: assigning unique codes to respective wireless power receiverdevices comprising the wireless power receiver device, wherein a uniquecode of the unique codes facilitates the receiving of the broadcast fromthe wireless power receiver device.
 19. A non-transitorymachine-readable medium, comprising executable instructions that, whenexecuted by a processor of a power transmission system, facilitateperformance of operations, comprising: receiving, by a timingacquisition module (TAM) of the power transmission system via at leastone group of antennas of the TAM, a broadcast from a wireless powerreceiver device of the respective wireless power receiver devices,wherein the broadcast comprises an encoded beacon, and wherein thebroadcast represents that the wireless power receiver device hasrequested power; in response to extracting, by the TAM, anidentification of the wireless power receiver device from the encodedbeacon, communicating, by the TAM to a device of the power transmissionsystem, a notification that comprises the identification of the wirelesspower receiver device and that indicates that the wireless powerreceiver device has requested power; and based on the identification ofthe wireless power receiver device, transmitting, via the powertransmission system using the at least one group of antennas of the TAM,wireless power signals to the wireless power receiver device.
 20. Thenon-transitory machine-readable medium of claim 19, wherein theoperations further comprise: receiving signals transmitted fromrespective wireless power receiver devices comprising the wireless powerreceiver device at antennas of the at least one group of antennas of theTAM; determining, for the wireless power receiver device, an antenna ofthe antennas that has received a signal of the signals having a signalstrength that is higher than respective signal strengths of remainingsignals of the signals other than the signal; and using a channelassociated with the antenna to communicate with the wireless powerreceiver device.